Audio Hungary Qualiton Phono
Overview
Meet the next evolution in our reference phono preamplifier design: the all-new Qualiton Phono! Building on the legacy of its predecessor, we've completely redesigned the MM preamplifier, drawing inspiration from the much-loved MM circuits of our C200 preamplifier. With the addition of 6SL7GT tubes, we've not only refined the sound character but also elevated the aesthetics to new heights. It now comes with an integrated MC step-up transformer by default, and its footprint is more compact, thanks to the sophisticated layout design.
6SL7GT Vacuum Tubes
The 6SL7GT is a dual triode vacuum tube, widely used in high-fidelity audio applications. Known for its warm and smooth sound character, it's a favorite among audiophiles for its ability to enhance the tonal quality. The 6SL7GT offers a balanced frequency response and excellent definition, contributing to a rich and detailed soundstage.
Custom Power Transformer
Just like our output transformers, our power transformers are also custom-designed and built in our in-house transformer workshop. We manufacture them with the same precision and attention to details: the high-permeability, large cross-section toroidal cores are also impregnated, and then the winding process follows. The parameters of the windings are designed to avoid saturation of the magnetic core and to ensure efficient operation even under heavy load conditions. It is important to note that we use double electromagnetic shielding for our power transformers. Finally, we employ the same epoxy compound used to pot the output transformers to eliminate mechanical vibrations and associated noises.
MM Phono Preamplifier
Over a decade ago, we embarked on our journey with our first MM phono preamplifier prototype. Since then, we've continuously refined these circuits to achieve exceptional sonic and technical performance. We're especially proud of the MM phono preamplifier of the Phono, which represents the pinnacle of our efforts, offering magical sound quality and solid measured performance. This version, featuring only vacuum tubes and passive elements, embodies absolute tonal purity and honesty.
MC Step-Up Transformer
In addition to the MM preamplifier, we integrated MC step-up transformers into the circuit design. These transformers, made in our in-house factory, were optimized for perfect synergy with the other subcircuits. Placing them inside the device without compromising the sensitive MC circuits due to magnetic fields from the mains and power supplies was a significant challenge. To address this, we covered the MC step-ups with high-permeability magnetic shields.
MC Cartridge Termination
We simplified the selection of the cartridge termination impedance after finding that too many options confused users. With the current model, users can choose between two settings: the Lo-Z position, recommended for MC cartridges with an internal impedance of 2 to 10 Ohms, and the Hi-Z position for 10 to 40 Ohms. While these are recommendations, users are free to choose between these options.
Optimized Layout
Maintaining a low noise floor while positioning the electron tubes of these sensitive circuits on top of the chassis was quite a challenge. We took every measure to ensure users can admire these tubes' appearance while keeping noise levels minimal. Extensive electrostatic and magnetic shielding protect the device's sensitive points. Additionally, the previously external power supply is now integrated into the device. It features a shielded R-core power transformer, and all DC voltages are stabilized to prevent unwanted signals from modulating the audio signal.
Protective Features
For enhanced reliability, we've included a delay circuit that activates the outputs after a 30-second warm-up period. Additionally, it monitors the mains supply and immediately disconnects the outputs if there is a sudden power loss, eliminating pop-up noises during power cycles.
Special Components
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Tested and Selected Vacuum Tubes
The preamp tubes are selected for low noise, symmetry and minimum distortion.
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Gold-Plated Ceramic Tube Sockets
Ensuring reliable connections. -
Gold-Plated Audio Terminals
Enhancing signal transmission quality. -
Film Capacitors
We exclusively use film capacitors in our audio circuits for optimal performance. -
Ceramic Composition Resistors
These resistors are placed in critical positions to enhance reliability. -
Long-Life, High-Temperature-Tolerant Capacitors
Employed in our power supplies to withstand demanding conditions.
Aesthetics
Our approach to the visual design centers around maintaining visual neutrality. We intentionally avoid overdesigning the appearance, aiming for aesthetic simplicity and cleanliness. Our products are not meant to be theatrical or ostentatious; rather, they seamlessly integrate into the audio system's interior without disrupting the user experience. However, we add unique touches that make our devices instantly recognizable.
Tech Specs
Electrical
0.4 millivolts to nominal output level (MC Hi-Z)
0.3 millivolts to nominal output level (MC Lo-Z)
20 Hz - 22 kHz bandwidth, without weighting filter, with tube cover installed
> x dB below rated output (MM)
with A-weighting filter, with tube cover installed
2 - 10 Ohm (MC Lo-Z)
+65 dB (MC Hi-Z)
+68 dB (MC Lo-Z)
General